Pump for a Domestic Appliance

ABSTRACT

A circulation pump for a domestic appliance, including a motor body, a motor, a hydraulic body attached to the motor body and including an inlet and an outlet, and a closure mechanism or member attached to the hydraulic body, a hydraulic chamber where the fluid flows, which is delimited between the hydraulic body and the closure mechanism or member. The pump includes an impeller housed in the hydraulic body and rotating, causes a substantially circular flow of the fluid in the hydraulic chamber, and a stationary element suitable or configured for aiding in discharging the fluid from the pump. The stationary element may be attached to at least one of the elements demarcating the hydraulic chamber and may be arranged in the hydraulic chamber such that it blocks or resists against the flow of the fluid.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application relates to and claims priority from Spanish Patent Application No. 201231732, filed Nov. 12, 2012.

FIELD

The present disclosure is related to circulation pumps for a domestic appliance, particularly in typical examples for a dishwasher.

BACKGROUND

Known circulation pumps typically include a motor assembled in a motor body, a hydraulic body fixed to the motor body and include a water inlet passage and a water outlet passage, and an impeller driven by the motor, which is housed inside the hydraulic body.

Known circulation pumps typically include a motor body, a hydraulic body, a motor and an impeller. The hydraulic body and the motor body are attached to one another, forming the body of the pump. The motor is housed in the motor body, and the impeller is arranged and centered on the base of the hydraulic body and is driven by the motor. The impeller rotates with respect to an axis of rotation when it is driven by the motor, and its rotation causes a substantially circular flow of the water inside the hydraulic body around the axis of the impeller, aiding in suitably discharging the water from the pump in a substantially tangential manner.

It has been seen in some pumps that when air together with the corresponding water or fluid gets in them, a circulation of air bubbles is generated due to the impeller. These bubbles are not always correctly discharged from the pump and form a type of circulation tube that significantly reduces pump efficiency, and can even cause the pump to be incapable of discharging the water it receives.

Pumps in the state of the art are known to be designed to solve this problem. Document US 20120224957 A1 discloses a pump of this type. This pump includes a circular guiding device arranged around the axis of rotation of the impeller, and the guiding device in turn includes a plurality of blades distributed in a circular manner. The blades are elastic and deform a specific angle according to the force of the water that entered in the pump, thus improving the fluid circulation and discharge according to its characteristics.

Document U.S. Pat. No. 5,451,139 A discloses a pump with a bladed impeller having a peripheral diffuser with a plurality of outlet ports and an interspace to convey the fluid from the outlet ports of the diffuser towards an outlet of the pump. This pump further has a curved member extending from the diffuser and arranged in the interspace such that it pushes the fluid upwards towards the outlet to discharge it from the pump.

Document US 20120224961 A1 discloses a pump with an impeller arranged at the base of the hydraulic body. This pump has a plurality of stationary blades which are arranged around the impeller, extending in a circular manner around the impeller and including a helicoidal shape. The blades are arranged in a carrier ring extending radially outside the impeller, surrounding said impeller, and are separated from one another by a specific distance in the rotating direction of the impeller.

SUMMARY

A pump hereof is suitable for a domestic appliance, often typically for a dishwasher. Such a pump includes a motor body, a motor housed in the motor body, a hydraulic body that is attached to the motor body and includes a fluid inlet passage and a fluid outlet passage, and a closure mechanism that is attached to the hydraulic body, a hydraulic chamber where the fluid flows inside the pump from the time it enters through the inlet passage until it exits through the outlet passage being delimited between the hydraulic body and the closure mechanism.

Such a pump hereof may further include an impeller driven by the motor which is housed at least partially in the hydraulic body and which, when driven by the motor, rotates with respect to an axis of rotation, causing a substantially circular flow of the fluid in the hydraulic chamber, and a stationary element which is suitable for aiding in discharging the fluid flowing in the hydraulic chamber from the pump through the outlet passage of the hydraulic body.

The stationary element may be attached to at least one of the elements delimiting the hydraulic chamber and may be arranged in the hydraulic chamber such that it blocks or resists against the flow of the fluid. As a result of the resistance exerted by the stationary element turbulences are generated, said turbulences channeling the air that may be introduced together with the fluid in the hydraulic body in a simple and natural manner out of the pump, without having to additionally incorporate additional parts or elements for bearing the stationary element. This may also include, for example, a simpler mounting of the pump and a lower cost for same.

These and other advantages and features will become evident in view the drawings and the detailed description hereof set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a preferred implementation of the pump hereof, where a section has been made in a hydraulic body of the pump.

FIG. 2 shows schematically and by way of example a closure mechanism of a pump hereof.

FIG. 3 is a plan view of the hydraulic body of the pump of FIG. 1, where a stationary element is shown.

FIG. 4 is a plan view of the hydraulic body of another embodiment of a pump hereof, where a stationary element is shown.

DETAILED DESCRIPTION

The fluid circulation pump 100 shown in the drawings may be suitable for a domestic appliance, typically for a dishwasher. The fluid is preferably water, and this term will be used hereinafter for the sake of clarity but without being limiting, although if necessary it is evident that a pump 100 hereof could be used with another type of fluid, preferably a liquid (although it could have solid or quasi-solid residues).

The shown pump 100 includes a motor body 1, a motor housed in the motor body 1, a hydraulic body 3 attached to the motor body 1, and a closure mechanism or member that is attached to the hydraulic body 3, the closure mechanism preferably being arranged between the motor body 1 and the hydraulic body 3 such that both bodies 1 and 3 are attached to one another by the closure mechanism (although this is not mandatory, the bodies 1 and 3 being able to be attached directly to one another, the closure mechanism even being arranged between both bodies 1 and 3, being attached at their ends for example). FIG. 1 shows a preferred implementation of the pump 100, where a section of the hydraulic body 3 has been made to show the pump 100 more clearly.

A hydraulic chamber 6 where the fluid flows inside the pump 100 is delimited between the hydraulic body 3 and the closure mechanism, and the hydraulic body 3 includes an inlet 30 through which water enters the hydraulic chamber 6 and an outlet 31 through which water exits the hydraulic chamber 6 and therefore the pump 100. The closure mechanism can include, for example, a cover 7 and a sealing element 8 (a gasket for example) for a leak-tight sealing of the connection between the cover 7 and the hydraulic body 3, shown schematically and by way of example in FIG. 2, the hydraulic chamber 6 being closed in a leak-tight manner except for the inlet 30 and the outlet 31.

The pump 100, as shown, further includes an impeller 4 which is driven by the motor and may be as shown housed at least partially and with rotational freedom in the hydraulic chamber 6. When driven, the impeller 4 rotates with respect to an axis of rotation 4 b, causing a substantially circular flow of the water in the hydraulic chamber 6, aiding in suitably discharging the water from the pump 100 through the outlet 31. The outlet 31 is preferably arranged such that the water is discharged from the pump 100 in a substantially tangential manner.

The axis of the inlet 30 preferably corresponds with the axis of rotation 4 b of the impeller 4, whereas the outlet 31 may have an axis in a different plane than the axis of the inlet 30, the outlet 31 preferably being arranged such that the water is discharged from the pump 100 in a substantially tangential manner. The water enters through the inlet 30, and exits through the outlet 31 driven by the impeller 4.

In some cases, generally due to a low level water at its source (generally a suction tank), water can enter a pump generally being mixed with air. In these cases, a circulation of air bubbles is generated in the hydraulic chamber of the general pump, and these bubbles cannot always be correctly discharged from such a pump, forming a type of circulation tube in the hydraulic chamber that significantly reduces the efficiency of such a pump and in some cases can even cause such a pump to be incapable of discharging the water it received.

Pump 100 hereof, however, may further include a stationary element 5 which is suitable for aiding in discharging the water circulating in the hydraulic chamber 6 from the pump 100 through the outlet passage 31, so that the pump 100 is capable of discharging the water even when it is mixed with air. The stationary element 5 may here, as shown, be attached to at least one of the elements demarcating the hydraulic chamber 3, i.e., to the hydraulic body 3, or to one of the elements forming the closure mechanism, or it can even be integrated in said element, being part of it. In the preferred implementation, the stationary element 5 is integrated in the hydraulic body 3, being part of the hydraulic body 3, as can be seen in FIG. 3. In other embodiments, the stationary element 5 could be attached to the hydraulic body without being integrated in it, or it could even be attached to (or integrated in) the cover 7 or it could be attached to the sealing element 8 (or integrated in the sealing element 8).

The stationary element 5 may be arranged in the hydraulic chamber 6 such that it is capable of or configured for blocking or resisting or blocks or resists against the flow of the water when said water is circulating in the hydraulic chamber 6, and extends at least partially along the width of the hydraulic chamber 6, although it could also extend along the entire width of the hydraulic chamber 6. As a result of the resistance exerted by the stationary element 5, turbulences are generated, said turbulences channeling the air that may be introduced in the hydraulic chamber 6 in a simple and natural manner out the pump 100, without having to additionally incorporate additional parts or elements for bearing the stationary element, and without the normal operation of the pump 100 (without the presence of air) being significantly affected.

The stationary element 5 may thus act like a wall for the water, blocking or resisting against its flow, generating a difference in pressures between two adjacent zones of the hydraulic chamber 6, each of the two zones corresponding with a zone on each side of the stationary element 5. The difference in pressure between both zones next to the stationary element 5 creates a zone with kinetic turbulence energy or favors turbulent flow, which in turn favors the rapid transition of air towards the outlet 31 through which it is discharged from the pump 100, the pump 100 significantly maintaining its efficiency even in response to the presence of air inside it (in the hydraulic chamber 6).

The stationary element 5 may include a corresponding respective side surface 51 and 52 facing each side zone between which the difference in pressure is generated, and both side surfaces 51 and 52 can be parallel straight surfaces, as shown by way of example in FIG. 4, wedge-shaped straight surfaces or even inverted wedge-shaped straight surfaces.

The water flows in a substantially circular manner around the axis of rotation 4 b of the impeller 4 in the hydraulic chamber 6 due to the action of the impeller 4, until leaving the hydraulic chamber 6 through the outlet 31. In a preferred embodiment, the stationary element 5 is arranged in the zone of the hydraulic chamber 6 closest to the outlet 31, and particularly at or after the outlet 31. In other embodiments of the pump 100, the stationary element 5 can be arranged in other positions inside the hydraulic chamber 6, but its efficiency may drop as it moves away from this preferred position.

The stationary element 5 can be attached at a first end to a wall of the corresponding element delimiting the hydraulic chamber 6, as occurs in the preferred embodiment where said element further corresponds with the hydraulic body 3. Said wall corresponds with the wall farthest from the impeller 4 delimiting the hydraulic chamber 6, and the stationary element 5 extends towards the inside of the hydraulic chamber 6 to block or resist against the flow of water. The second end of the stationary element 5 opposite the first end is the point of the stationary element 5 closest to the impeller 4. The stationary element 5 can extend inwardly into the radial hydraulic chamber 6 with respect to the axis of rotation 4 b of the impeller 4, but it does not necessarily have to. In fact, in the preferred embodiment this does not occur, as shown by way of example in FIG. 3, for example. 

1-13. (canceled)
 14. A pump suitable for a domestic appliance comprising: a motor body; a motor housed in the motor body; a hydraulic body attached to the motor body and comprising a hydraulic chamber with a fluid inlet and a fluid outlet; an impeller at least partially housed in the hydraulic body and coupled to the motor, the impeller arranged to rotate with the motor with respect to an axis of rotation, upon rotating the impeller is configured to cause a substantially circular flow of the fluid in the hydraulic chamber; and a stationary element being arranged in the hydraulic chamber located in the fluid flow path of the fluid, the stationary element configured to induce a type of turbulent flow of the fluid in the hydraulic chamber that enhances the pump's ability to transition an air in the fluid toward the fluid outlet.
 15. A pump according to claim 14, wherein the stationary element is arranged in the hydraulic chamber at or near the fluid outlet to induce a type of turbulent flow of the fluid at or near the fluid outlet that enhances the pump's ability to transition an air in the fluid toward the fluid outlet.
 16. A pump according to claim 14, further comprising a closure member disposed between the motor body and the hydraulic body, the closure member being attached to the hydraulic body and forming at least a portion of the hydraulic chamber.
 17. A pump according to claim 14, wherein the stationary element comprises a first side and a second side and generates a difference in pressures between adjacent first and second zones of the hydraulic chamber, each of the first and second zones corresponding respectively to the first and second sides of the stationary element.
 18. A pump according to claim 14, wherein the stationary element is formed as a monolithic structure with the hydraulic body.
 19. A pump according to claim 14, wherein the stationary element is attached to the hydraulic body.
 20. A pump according to claim 16, wherein the stationary element is formed as a monolithic structure with the closure member.
 21. A pump according to claim 16, wherein the stationary element is attached to the closure member.
 22. A pump according to claim 16, wherein the closure member comprises a cover that is attached to the hydraulic body and a sealing element for the leak-tight sealing of the connection between the cover and the hydraulic body, the stationary element being formed as a monolithic structure with the sealing element.
 23. A pump according to claim 16, wherein the closure member comprises a cover that is attached to the hydraulic body and a sealing element for the leak-tight sealing of the connection between the cover and the hydraulic body, the stationary element being attached to the sealing element.
 24. A pump according to claim 14, wherein the stationary element is attached at a first end to a wall of the hydraulic chamber located farthest from the impeller with the stationary element extending towards the inside of the hydraulic chamber.
 25. A pump according to claim 24, wherein a second end of the stationary element opposite the first end is a part of the stationary element located closest to the impeller.
 26. A pump according to claim 14, wherein the stationary element extends at least partially along a width of the hydraulic chamber.
 27. A pump according to claim 14, wherein the stationary element extends along an entire width of the hydraulic chamber.
 28. A pump according to claim 14, wherein the stationary element is arranged in the fluid outlet.
 29. A pump according to claim 15, wherein the stationary element is formed as a monolithic structure with the hydraulic body.
 30. A pump according to claim 15, wherein the stationary element is attached to the hydraulic body.
 31. A pump according to claim 15, further comprising a closure member disposed between the motor body and the hydraulic body, the closure member being attached to the hydraulic body and forming at least a portion of the hydraulic chamber, the stationary element being formed as a monolithic structure with the closure member.
 32. A pump according to claim 15, further comprising a closure member disposed between the motor body and the hydraulic body, the closure member being attached to the hydraulic body and forming at least a portion of the hydraulic chamber, the stationary element being attached to the closure member.
 33. A pump according to claim 15, further comprising a closure member disposed between the motor body and the hydraulic body, the closure member being attached to the hydraulic body and forming at least a portion of the hydraulic chamber, the closure member comprising a cover and a sealing element for the leak-tight sealing of the connection between the cover and the hydraulic body, the stationary element being attached to the sealing element. 